1561623460 has 12 divisors (see below), whose sum is σ = 3279409308. Its totient is φ = 624649376.

The previous prime is 1561623403. The next prime is 1561623463. The reversal of 1561623460 is 643261651.

It can be written as a sum of positive squares in 2 ways, for example, as 1027458916 + 534164544 = 32054^2 + 23112^2 .

It is not an unprimeable number, because it can be changed into a prime (1561623463) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39040567 + ... + 39040606.

It is an arithmetic number, because the mean of its divisors is an integer number (273284109).

Almost surely, 2^1561623460 is an apocalyptic number.

1561623460 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1561623460 is an abundant number, since it is smaller than the sum of its proper divisors (1717785848).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1561623460 is a wasteful number, since it uses less digits than its factorization.

1561623460 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78081182 (or 78081180 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 34.

The square root of 1561623460 is about 39517.3817452523. The cubic root of 1561623460 is about 1160.1801791066.

The spelling of 1561623460 in words is "one billion, five hundred sixty-one million, six hundred twenty-three thousand, four hundred sixty".